Effect of wind speed and direction on convective heat losses from solar parabolic dish modified cavity receiver

Abstract The performance of solar parabolic dish collector is significantly influenced by heat losses due to wind speed and direction. In this article, investigation of convective heat losses from the modified cavity receiver of solar parabolic dish collector is carried out numerically by considering the wind direction, wind speed, receiver configuration and receiver orientation. The effect of wind on the receiver in various directions ( φ  = −90° to 90°), wide range of operating wind speeds ( V  = 0–10 m/s), receiver inclinations ( β  = 0–90°) and varying surface temperature on convective heat loss from the receiver are studied. Velocity vectors, velocity contours, temperature contours are presented to show the effect of wind on the heat loss from the modified cavity receiver. The forced convection is found to have similar trend of free convection heat loss at lower wind speed. However at higher wind speed, such a pattern is not observed. At lower wind speeds say less than critical wind speed ( φ and β values. For side-on winds, at higher wind speeds above 5 m/s, irrespective of receiver inclination, the variation of forced convection heat loss is marginal (less than 5%). The maximum forced convection heat loss occurs for partly open receivers (receiver aperture diameter ratio, R AD  = 0.4 and 0.6) at φ  = 0 (side-on wind) for all receiver inclinations and at φ  = 30° for R AD  = 0.8 and 1. The receiver inclination has less effect on heat loss from the receiver for V  > 2.5 m/s due to side-on wind. The highest convection heat loss occurs for fully open ( R AD  = 1) receiver as compared to partly open ( R AD